Electric vehicle

ABSTRACT

An electric vehicle capable of maneuvering in restricted areas through the use of a single steerable drive wheel mounted on a circular bearing assembly, which has a groove therein for receiving a cable so that by pulling the cable the steering wheel can be rotated. The electric vehicle has outwardly extending stabilizing members mounted on the frame adjacent the steering wheel so as to prevent the vehicle from turning over when such is cut too sharply. The vehicle is driven by an electric motor which is powered by a DC battery having a plurality of cells. A switching circuit is provided for sequentially converting a parallel connection of the cells to a series connection so as to vary the voltage supplied to the motor by simple manipulation of a single handle. The battery is carried within a pack so that such can be removed from the vehicle, and another battery pack substituted therefor, while such is being charged. Positioned adjacent the rear of the vehicle is a pivotal platform upon which the operator stands while driving the vehicle. A braking shoe is coupled to the pivotal platform so that when the operator shifts his weight forward on the platform such engages a wheel, stopping the vehicle. However, if the operator shifts his weight to the rear, the braking shoe will be raised off the wheel permitting the vehicle to move. The position of the rear axle of the vehicle can be readily adjusted by merely manipulating a locking mechanism and shifting the axle to the desired position.

United States Patent [72] Inventor James T. Triplett Primary Examiner-Kenneth H. Betts Shamrock Drive, Chester, S.C. 29706 Attorney-Bailey & Dority [21] App1.No. 727,271 [22] Filed May 7,1968 Patented Mar-2,1971 ABSTRACT: An electric vehicle capable of maneuvering in restricted areas through the use of a single steerable drive wheel mounted on a circular bearing assembly, which has a groove therein for receiving a cable so that by pulling the cable the steering wheel can be rotated. The electric vehicle has outwardly extending stabilizing members mounted on the frame adjacent the steering wheel so as to prevent the vehicle 1 from turning over when such is cut too sharply. The vehicle is [541 ELECTRIC VEHICLE driven by an electric motor which is powered by a DC battery 3 Claims, 11 Drawing Egg having a plurality of cells. A switching circuit 18 provided for sequentially converting a parallel connection of the cells to a [52] U.S.C|. 180/26, series connection so as to vary the voltage supplied to the 280/92, 180/52, 180/65, 280/30 motor by simple manipulation of a single handle. The battery [51] Int. Cl. 862d 9/00 is carried within a pack so that uch ean be removed from the Fiflld ofSeal-ch 180/26 vehicle, and another battery pack substituted therefor, while (Cursory), 65, 25, 27, 52; 280/92; 280/ 150, such is being charged. Positioned adjacent the rear of the vehi- 56 R r cle is a pivotal platform upon which the operator stands while 1 e erences driving the vehicle. A braking shoe is coupled to the pivotal UNITED STATES PATENTS platform so that when the operator shifts his weight forward 1,001,837 8/1911 Fuller 180/52 0n the platform such engages a wheel, stopping the vehicle. 1,311,032 7/1919 Arpin 280/92 However, if the operator shifts his weight to the rear, the brak- 2,767,995 10/1956 Stout 280/ ing shoe will be raised off the wheel permitting the vehicle to 3,193,040 7/1965 Loomis /26X move. The position of the rear axle of the vehicle can be readi- ,2 37 11/ 1965 Appleton... 180/26 ly adjusted by merely manipulating a locking mechanism and 3,416,625 12/1968 Narutani 180/5 2X shifting the axle to the desired position.

80 a? E u H 68 x" 69 65 I81 R P 56 i e l o o 1;; i I l i I l B l 5 12 .2 92 22 I I O 1 I 0 e3 o o o I l L 4'9 1*" a4 3 30 A 42 :5 72

warm am 21971 SHEET 2 OF 4 INVENTOR.

\JAMES T. TRIPLET'T A TTORNE YS.

PATENTEUHAR 2m 3566385 sum 3 (M JAMES T; TRIPLETT a g vi" r a BY I19: 6.

0 1e". 57 INVENTOR.

ATTORNEYS.

ELECTRIC-VEHIC E Thisinvention relates to an electric vehicle, and-moreparticularlyto anefftcient and readily maneuverableelectric vehicle. 7

One of the problems encountered in industrial vehicles is that they are difficult to maneuver in restricted areassuchas in narrow-aisles of buildings ln an attemptto minimize the problem three-wheeled vehicles have beendeveloped wherein a single steerable driving wheelissued so as to produce a short turning radius. Such does produce, a short turning radius and, thus does increases the maneuverability of the vehicle, .how-

ever, italso increase the possibility that the vehiclewill tilt or turn over when such is turned sharply,

Another problem encounteredin electric vehicles, such. as

golf carts, .is overheating @when the vehicles is run .at slow speeds Such is frequently due to the variableispeed controls .which are used, which normallyineorporates. a .variablepre- .sistance element for controlling thevvoltagmbleing,suppliedto the motor. This type of control not onlyshortens ,thecha fged life of the batteriesbeing used, but also have a; substantial heat in an arrested condition so .as-to prevent the vehicle "from rolling freely. The electric controls on the'vehicle should-also be designed so that when the operator removes his hand orthe like, therefrom, the vehicle should be stopped.

In order to minimize the above-mentioned. problems, one particular electric vehicle constructed in accordance withfthe present invention has a steerable drive wheel :which is mounted adjacent the front of the frame of the vehicle so that the vehicle canbe readily :maneuverednAdjacent the reano'f the vehicle is a pair of adjustable wheels. Alpairiof stabilizing membersextend laterally from the frameof the vehicleladjacent the front steerable wheels so that if the vehicle tilts during operation, the stabilizing wheel will engage the surface,

preventing the vehicle from turning ov er. ,Thus, thevehiclels readily maneuverable and can be used in restrictive areas,:-.and is still safe to operate. The vehicle is clriven-iby a DC electric motor which is powered by a DC battery having a plurality of cells. A switching circuitry isprovided so that the cells canfbe sequentiallyconverted from a parallelconnection to a series connection to increase the voltage beingsuppliedtothe motor, and, thus increase the speed that the vehicle is traveling. By connecting the motor to the battery in suc'h a manner there is substantially no power lost in varyingthcspeed of the vehicle. Another feature of the vehiclewwhich simplifies itsiconstructio n, is that it is steered by means of. manipulating a cable which is wrapped around a portion of a, circular ballbearing member upon which the steerable driving wheel is carriedgBy pulling the cable by turning a steering wheel, thelsteerable drive wheel may be turned accordingly, for guidin g thevehicle. in order to prevent accidental energization of the vehicle a pivotal platform is provided to the rear-ofthe ,vehiclexto which a braking shoe is coupled. Whenthe operator places his weight at the rear of the platform such causes the braking element to. move out of engagement with the wheels of the vehicle allowing such to move. When the operator steps off ,the vehicle a spring causes the platform topivot sotthatthe braking element is inengagement with the wheel preventingsuchfrom moving forwardrln order that thevehicle not be tied up while recharging the battery such is carried in a readily removable pack which plugs into the vehicle. An identical packcan be substituted therefor, so wthatthe vehicle is ready for use at all times.

. wheels,

lustrating the drivable steering-wheel,

-.capable of riding on surfaces which includeaframe A. A sin- Accordingly, animportant object ofthe present invention is to .provide a vehicle which is it readily maneuverable in restricted areas, whichis relatively safe from tumingovenand is simple to operate.

. Another important object ofthe present invention is to provide an electric vehiclewhich is relatively simple to construct and can be operated with a minimum amount of power loss.

Another important objectof thelpresent invention is toprovidean industrial vehicle which has controls and a braking .mechanism-which;preventsaccidental operation or rollingof ,the vehicle when not under the control of an operator.

Still another-important objectof the present invention is. to

provide ,avehiclewithwheels, the position of which can .be

readily adjusted. so'..as"-;to.distributethe load..on the framelin .ordento maintainproper traction-for the drivinglwheel.

Still a-furtherimportant object of the present invention is to .;provide an electric vehicleas aforesaid, in whichthe components'are of sufficientsimplicity .tomakepossible economical fabrication. a

-A1further objectofithepresent invention is topprovide an electric'vehicle whichis strong andsturdy, and will withstand long andrigorous use.

.The constructiongdesigned to carry out the inventiontwill be hereinafterdescribed,together with other-features thereof.

.The inventiontwill be morereadily understood from a reading of the following specification and by'reference to themcompanying.drawingsforming apart ;thereof,-wherein an ex- .ampleof the. invention is. shown and wherein:

FIG. 1 is a plan view withythe-body ofthe vehicle removed,

' to illustratetheworking mechanism therein,

EIGIZ is a side elevational view; partially in section, FIGS. 3, 4, 5 and 6 are planviewsillustrating theswitching "circuit in various positions for supplying voltage to the-electric I motor of the vehicle ,FIG. 7 is an enlarged elevationalview illustrating aportion of,the1battery pack for thevehicle and the rear wheel assembly of such, taken'along line 7-7 of FIG .8,

FIG. 8 is a sectional view taken along lined-8 of H032, illustrating the mechanism for shifting the position of. the rear FIG. -9 is a sectional view taken along line 99 of FIG. ,2, lil- LFIGJIO is a sectional view illustrating-a portion of the circularlbearing member upon which the steerable drive wheel is carried, and

(FIG. 11 is a schematic diagram illustrating the electrical circuit for said vehicle.

The drawings illustrate .a self-propelled electric vehicle gle steerable drive wheel B is carriedadjacent one end of the (frame in engagement withflthe surface uponwhich .thevehicle is traveling,andsupports that'particular end of the vehicle. A pairof wheels arecarried on the opposite end of the-frame from the steering wheel B in engagement with the surface upon which the. vehicle is traveling for supporting the opposite .end'of thevehicle. T he vehicle is driven by .aDC motoriD which is, in \turn, powered .by a battery E carriediby the frames; Laterally extending stabilizing members -F.ar.e..carried by the frame adjacentandon opposite sides of the steering wheel B. The stabilizing members are spaced vertically from the surface uponvwhich the vehicle is riding, but engage'the surface when thevehicle tilts to one side preventingsuch from turning-over. Anaxle uponwhichthe single steerable drive wheel B iscarried is-mountedon achannel member ofagpair of circular ,angle members G which arein juxtaposition, and have ball bearings carried therebetween for allowing one member to rotate relative to the other in orderthat the vehicle ,can be steered: during operation. A switching circuit His interposed betw eenathe battery and the motor for-sequentiallyconvetting the cells of the battery from a parallel connection to a series connection inorder to increase the voltage .appliedzto the motor.

The frame A is constructed primarily of steel in the form of angle iron and the like, and is substantially rectangular in shape having a vertical front frame portion 10, the upper end of which is integral with the horizontal main body portion 11 which extends over the front steering wheel, the battery E, and the rear set of wheels. Adjacent the rear ofthe main body portion 11 is suitable framework 12 upon which the platform on which the operator stands is mounted. A vertical standard 13 extends upwardly from the main body portion of the frame 11 for accommodating the steering wheel 14 and a throttle 15, which is used for controlling the speed of the vehicle.

A fiberglass housing 16 encloses the upper portion of the framework and is bolted thereto by bolts 17. The fiberglass housing has a vertical front wall 18, the upper end of which is integral with a flat horizontal portion 19 which extends across the top of the horizontal main body portion 11 of the frame and is bolted thereto. The housing has opposed sidewalls 20 extending downwardly from the flat horizontal portion 19 which terminate adjacent or slightly below the bottom of the frame. The portion of the housing integral with the rear of the horizontal portion 19 has a recess 21 therein, which permits an operator to stand on a pivotal platform 22 when operating the vehicle. One of the sidewalls 20 also has a hinged panel therein (not shown) which can be readily raised for removing the battery pack from the vehicle in order to substitute another therefor.

The drivable steering wheel B is carried Within rectangularshaped framing which includes the from frame portion and a portion of the horizontal main bottom body 11 from which downwardly extending vertical angle irons 23 are connected adjacent the sidewall of the framework. A pair of opposed channels 24 extend from adjacent the base of the vertical angle irons 23 to the front frame portion 10.

The steerable drive wheel B and the DC motor D are mounted on the circular bearing member G so that they rotate simultaneously therewith. The steerable wheel B has an enlarged sprocket 25, attached thereto, through a bearing 26 so that by rotating the sprocket such, in turn, rotates the wheel B. An axle 27 extends through the wheel B, the bearing 26, and the sprocket so that such can rotate thereon. The ends of the axle 27 extend between opposed vertical braces 28 and are flxed thereto, by nuts 29. The DC motor D is mounted on the upper ends of the vertical braces 28 so as to allow such to rotate with the wheel B. The lower ends of the vertical braces 28 are secured to the vertical flange of a cross angle iron 30 by any suitable means, such as by welding. The cross angle irons 30 are, in turn, bolted between opposed sides of the lower movable portion of a bearing assembly G. A more detailed showing of the bearing assembly G is illustrated in FIGS. 1, 2, 9 and 10. The circular bearing assembly G is constructed of two pieces of circular angle members 31 and 32, respectively. The opposed circular angle members 31 and 32 are in juxtaposition so as to define a circular channel in which ball bearings 33 are positioned for maintaining the two members 31 and 32 apart and for allowing the lower member 32 to rotate relative to the upper member. The upper channel member 31 has a downwardly extending portion 34 which has a locking abutment 35 projecting inwardly adjacent the lower portion of the sidewall thereof. The lower angle member 32 has an upwardly extending portion 36 adjacent its inner perimeter which, in turn, has an inwardly projecting locking abutment 37 projecting from the sidewall thereof, so that when the ball bearings 33 are placed in the circular channel such permits the lower angle member 32 to rotate relative to the upper angle member, and also prevents the angle members from separating. The ball bearings 33 are loaded into the circular channel by means of a hole 38 extending through the upper angle member and communicating with the circular channel. This hole is normally closed by means of a bolt 39. At one point on the lower angle member a portion of the locking abutment 37 is removed so that the ball bearings can be dropped through the hole 38 into the channel. When the nut is returned to position, as shown, such prevents the ball bearings from coming out of the bearing assembly.

As previously mentioned, the angle irons 30 upon which the drive wheel B and the motor D are mounted are, in turn, mounted between opposed sides of the lower angle member 32. The upper angle member is, in turn, bolted to the angle irons 24 which are carried on the side of the frame between the from frame portion 10 and the vertical angle irons 23.

A groove 41 is provided in the outer perimeter of the lower angle member 32 of the bearing assembly G for receiving a cable 42 which is wrapped therearound. Thus, by pulling the cable 42 such, in turn, rotates the lower angle member 32 causing the wheel B to rotate accordingly. Therefore, the vehicle can be readily or easily manipulated in restricted areas by means of the cable 42.

The cable is an endless cable and one side of such extends under a pulley 43 rotatably mounted on the brace 24, over the pulley 44 carried adjacent the top of the frame, under the pulley 45 adjacent the vertical standard 13, through the framework of the standard 13, and is then wrapped around the grooved body portion 46 of the steering wheel so that when such is rotated the cable is taken up on one side and let out on the other. The other side of the cable extends from the steering wheel 14 and is returned to the bearing assembly G via pulleys 45, 44 and 43, which correspond to the pulleys carried on the opposite side of the frame.

The DC motor D may be any suitable conventional electric motor which can be operated by voltages from'6 to 24 volts. The drive shaft 47 extends outwardly from the motor D and has a sprocket 48 mounted thereon. A chain 49 is mounted between the smaller sprocket 48 and the large sprocket 25 so that when the drive shaft 47 of the motor is rotated such, in turn, causes the drive wheel B to be rotated in order to propel the vehicle. It is noted that during the steering operation the motor assembly rotates with the steering wheel B.

The rear end of the vehicle is supported on a pair of wheels C. The wheels C are carried between oppose rear side frame members, each of which includes a brace 50 which is integral with the lower end of the vertical brace 23, and extends under the battery E for supporting such and then turns upwardly as at 51, then rearwardly as at 52, terminating behind the rear wheels C. Suitable vertical side braces 53 and 54 have their lower ends integral with the horizontal rearwardly extending brace 52, and extend upwardly to join the rear end of the horizontal main body brace 11. Braces, such as the cross brace 55, also extend between the opposite side frames connecting such together adding strength and rigidity to the entire frame.

The axle 56 upon which the rear wheels C are carried is, in turn, carried within a pair of opposed brackets 57, each having an elongated slot therein so that the axle can beshifted longitudinally in order to change position of the wheels relative to the frame.

A plurality of spaced downwardly extending flange members 59 are pivotally carried adjacent each elongated slot 58 for locking the axle 56 into position relative to the frame between adjacent flange members. As shown in FIGS. 7 and 8, the upper ends of the flange members 59 are integral with the elongated rod 60 which has its ends journaled in laterally extending brackets 61 so that such can be pivoted from a downwardly extending vertical position where the axle is locked between the flange members 59 to a horizontal position where the axle can be shifted longitudinally within the slot 58.

The mechanism for pivoting the flange members 59 from the vertical position to the horizontal position is illustrated in FIG. 8, and includes a handle 62 which, when depressed, to the dotted line position raises, the flange members 59 to the horizontal position. The handle 62 has a horizontal portion 63 which is suitably journaled on the frame (not shown) so that when such is depressed it rotates an arm 64 which has one end pivotally connected to another linking arm 65 which has its free end pivotally connected to still another linking arm 66, which has its free end fixed to the rod 60. A spring 66 is connected between the frame and the lower end of linking arm 65 for maintaining the handle 62 in the raised position, as shown in FIG. 8. The other end of the arm 64 is pivotally connected toa linkingarmo'l which. has'its' free end pivotally. connected .tqthe linkinganni66 ontheother. side of the frameuwhichiin .turnv manipulates the other rodifilllf Thusnit. can: be .seen that when. the thandle. .62 isudep ressed; thevarm 64 is rotatedsima clockwise direction, and such rotation causes, the linking arm osto pivot one arm: 66 connectedto the ransom a clockwise direction raisinggthetflange members 59,0n the right-hand side of the frame as illustratcdin FlGwfi, from the fullline'yertical position to the broken linehorizontal position. The rotation of the lower end of-lthe lever.armt i inraclockwise direction causes the leverarm=66 onlthe tleftrhand pside ofuthe frame-to be rotated inacounterclockwisetdirectionpivoting the flange members; 59 on that side of the frame-in a clockwisedirection to the horizontal position as shown inbroken linesx'I-he reason that it is desirable that the rearwheelscan be adjusted,isithat when theretisno loadrcarriedton the vehicleandthe operator -places his weight onthe rearof the platformti22,.sometimes suchtwill cause the front of the vehicle to be raisedwofffthe sur- 1 faceupon which his riding; Since ,the;front1-wheeL B.istthefdriv- I ing wheel, such willimmobilize.the vehicleslilt isalsodesirable driving the vehicle. When he; places' -his weight. to. the reanof the platform such causesthe; braking shoes-68 IOl'bQ raisedvoff the trear .wheels C @llowing the ivehicleato: movemWheni-he shifts his weight forward or steps soff'dthei platform .E 22,'-.;su'ch causes the braking ,.shoes{-68- to .engage the wheels, tlthus stopping the VhlC16. Th platforntgZZ isllpivotallytmountedzon a cross. rod;69, (see F1677), whichsiscarried between theppposed vertical sidebraces-Sl: A spring 70- is carried tincorn .pression between the horizontal .braceb'SZ and'the platfonmtZZ so that when the operator steps from-Jthe-platform or;shiftsfa.his weight (forward, such. causes the platform to tilt fOITWflId'iO the position shown in FlGfl where .the-brakipg-shoesi68 are' irtgengagement with the wheels C.

1 lsinglezsteering wheel,- if such cannot be operated-safely; then? it isnot'practical.

, In order to minimizetthe possibilityof theevehicle turning .;.over laterally extendingistabilizingt members F are carriedlby .lthe frame adjacentandon opposite sides of the steerable drive twheelzB. The stabilizing membersazre spaced vertically from :;the. surface. upon twhichthe vehicle is riding, but engage the usurface when the vehicle tiltsto one side preventing the'vehicle fromturning overJSuchincludes.apair. of rollers carried onopposite ends of a shaftzfillwhich is suitably attached .tto the-frame of the vehicle. lt-is'noted that the rollers 80 are w-spaced above-thesurface upon which the front wheel B rides tsofthat theyonly come in=engageme=nt with the surface when the vehicle .tiltsfThe;edgesofthe rollers" 80tshould be beve'led sovthat :when such engage the surface they do. not; produce scratches: In some. embodiments; rather than 1 using the discshapedwrollers, .as';illustrated,..a "ball mounted :in a socket spaced laterally oftheframe and vertically from the surface .onrwhichsthe vehicle is riding can be used.

I In the embodimentillustrated in-FIGS. lr and 2, afiberglass tub-shaped receptacle is carried on the-housing 6" for receiv- .ing. the items :thatare toube transported by the vehicle. The receptacle -has;protrusions:83l on the bottom thereofuwhich' fit into, corresponding indentations in the top. ofthe housing 16 cfortholdingsuchrinplaceionthe vehiclekThe.receptacle'82 can The readily removed fromon top'oftlhe.housingandtaseat for accommodatingia passenger can be substituteditherefor.Z'Fhe seat :would be carried above; the front wheel assembly so .that the passengers legs are allowed to extenddownioverthe front .ofthe vehiclegand his feet rest on thespivotalxplatform 84. rlt is noted that when the platform is. not being'used such canzbe pivotedtota rventiealiposition since it is carried onL-ithe rod ,journaled betweenft'he side. of the" frame.

-A switchirigcircuit H :is interposed between -the::bat-tery E :and themotorrDforvarying the voltage suppliedtolthexmotor responsive tto manipulating the throttle lever E15. 'l -he switchingcircuit includes three switcheswhich caribe sequentially shifted from afirst operating positionto secondoperat- .Eachbraking shoe 68 is pivotal ly carried betweenapainof ingpositionQWhenthe first switch'R is closed 6 voltsiarempspacedlever arms7l each Ofawhichthaseits lower eridpivotally connected to the horizontal -brace' 5'2. The: r pper. ends roffthe ing strap (not shown), whichcouples:twooavolt.cells or units together to form the l2-voltbatteryflwhen'usedtto powercthe subject vehicle this connecting strapis cutrso that, inressence, there areifouri-volt cells,Blthrough flkwhich make upIthe battery.

The" two batteries-are carried within =a'battery p aolc,which includes a bottom with sidewalls "'18 extending upwardly volt conventional-batteries 77 eachiofwhichihave a connect.

therefrom about :halfway up .thenbatterycso aslo;provide.a

receptacle for holding or retainingtthetwo batteries therein-A handle '79extends upwardly from opposedsidetwalls78;.over

the top of the battery so that the'entire batterygpackcan be lifted from the frame .whendischargedinorder that, another fully charged battery can besubstituted thereforillt is noted that --the battery packtissupported on the1brace'50,-.and is prevented from moving by thebraces23=and 5'1.

IiQne of the problems encountered .in-three-wheeled vehicles isthan if. they are turned sharply-while the .vehicle is moving at .a fastrateof speed, it-will tend totilt .orqsometimes. turnover. While it. is desirable for purposespof maneuverability ,to-..use-a ;plied. to the..DC motor.-'since. the wiring-arrangement is .such -that-all fourofthe 6-volt cells are connectedin parallelfwhen the switching circuitlis in .theposition illustrated-in FIG.1l5 :where both switches RtandiS have beenclosed, then 1.2 volts 45 tare-applied to the .DOmotor. since thecells are conneoted -in groups of .a-pair of o-voltcells in parallel and these two; groups arethen connected in series so that l. 2" volts are applied to the motorQ -Whenallthreexof the switchesR, SandTare intheforiward'positione as illustrated in FIG. 6;;then all fourofrthe the 6-voltcells are connected in series andI24 voltsareappliedto :the DC motor. 'Thus,.the -vehicle hasethreespeedsH-A slow speed when the 6ivolts are applied to vthe-motor an intermediatespeedwhen 112 volts are applied to the xmotoru and a zhighuspeed -when'124 voltsare appliedto the-motor. The

switching circuittandathesvarious positionsof suchare illustrateci in FIGS. I3rthrough126 and a schematic-diagram:of the welectricaltwiringof the switches is illustrated inFlG. Ll/jibe switchingcircuit iszrnountejdbetween atpair of crosszbracesi86 andi'87, which are, inturn, carried between oppositesidesof the frame.Atpairof'opposed laterally-extending angle irons138 L and 89. areywlded between cross br.aces'.86 and 87 "and have ntheir vertical flange 90extending upwardly. Each of the-vertical flanges '90 has an elongated slot therein provided for actcommodatingtthe flat bar "member 91 and. permits-suchWto he moved from rairear position, such-as illustrated in FIG. T3,:toa

forward position, .such as illustrated in F1616. Pivotally .mountedionthe baramember9l is aIle-ver armQZLThe inner end of the lilevervarm 912 .is .pivotal'ly connected .to the :bar member 9:1-asatpivotjoint'93. The outer end of the .lever at m "92is connectedbyia-spring 94 to a laterally'extendinglbracket 94a. The spring 94 tends to maintainthe leveruarm i92 in i'the rear position,:suchasiillustrated in FIG. '3. Ahookzconnecting -element95 has .oneendconnectedto the leverarm wtandithe other :end. connected to *a cable 96, which has its free end threaded over pulleys, such as illustrated at 9'7, and connected to the throttle lever 15. When the throttle lever is pushed forward from the position illustrated in FIG. 2 such causes the cable to pull the lever arm 92 from the rear position illustrated in FIG. 3 to the position illustrated in FIG. 4 against the tension in the spring 94. It is noted that the bar member 91 is also connected by a larger spring 98 to the end of the laterally extending arm 94a. The spring 98 is connected to the bar member 93 offcenter so that when the throttle lever is depressed the cable 96 pulls one side of the bar member forward first, such as illustrated in FIG. 5, until such side'reaches the end of the slot and engages such, then upon depressing the throttle lever 15 further, such pulls the other side of the bar member 91 to the forward position, such as illustrated in FIG. 6. When the operators hand is removed from the throttle 15 the springs 98 and 94 return the bar member 911 and lever arm 92 to the rear position, as illustrated in FIG. 3.

It is noted that the lever arm 92 is notched so as to accommodate the movable switching element 99 of the switch R. The switch 8 is also fixed to the underside of the bar member 91 by any suitable means, such as screws, so that it moves with the bar member. The switching element 99 normally tends to tilt rearwardly except when engaged by the lever arm 92. The bar member 91 has apertures ltltl and ill]. adjacent the ends thereof, through which the switching elements 102 and 103 of switches S and T, respectively extend. Thus, it can be seen that as the cable 96 is pulled forward a small amount, the switching element 99 is moved to a forward position, then as the cable is moved further the left end of the bar member 91 moves forward shifting the switching element 102 from the the rear position to the forward position until the edge of the bar member 91 engages the end of the slot carried within the vertical flange 90. As the cable 96 is pulled further the righthand end of the bar member 91 is shifted to the forward position, in turn, shifting switching element I03 from the rear position to the forward position. The switches S and T are held in a fixed position between the cross braces 86 and 87. The spring 98 tends to bias the movable member 91 to a rear position and toward one side.

FIG. II is a schematic diagram illustrating the manner in which the vehicle is wired. The three switches R, S and T are illustrated on the left, while the four cells B B B and 5,, respectively, of the battery E are illustrated on the right. Each of the cells are 6-volt cells. A reverse switch U is also provided for reversing the polarity of the voltage being supplied to the motor D so that the vehicle can be either driven forward or reverse.

The switch R is a conventional switch having an On-Off position, and when such is in the position illustrated in FIG. 3, such is in the Off position, and when such is in the position as illustrated in FIGS. 4 through 6 such is in the On position. Switch S is a conventional four-pole double-throw switch having 12 terminals S through S respectively, thereon for the purpose of wiring. One suitable four-pole double-throw switch is manufactured by Arrow, Hart and Haggaman of Hartford, Conn. and has a Model No. 80999. Switch T is a two-pole double-throw switch having 6 terminals thereon, T through T respectively, and one suitable switch is manufactured by Arrow, Hart and l-laggaman of Hartford, Conn., and has a Model No. 81869. The location of the terminals on the switches illustrated in FIG. 11 is as appears when looking from the bottom of the switches. The switching elements 99, 102 and 103 for the switches would move from left to right and back when looking at FIG. 11.

Switch U is a conventional forward and reverse switch. When the switching element (not shown) is moved to the On position, a voltage of one polarity is applied to the motor, and when the switch element is shifted to the reverse position a voltage of the opposite polarity is applied to the motor. When the switching element is in the center the switch is in the Off position. The motor D is wired via leads 104 and 105 to the output of the reversing switch U. One input terminal of the reversing switch U is connnected via lead 106 to terminal T on switch T. The other input terminal of the reverse switch is connected via lead M7 to terminal R of switch R. Terminal R of switch R is a blank terminal, and terminal R, is connected via lead N93 to terminal T of switch T.

Referring now to switch S, it can be seen that terminal 5, is a blank terminal and terminal S is connected via lead 109 to terminal S Terminal 8;, is a blank terminal and terminal Sq is connected by lead in) to terminal S Terminal S is connected via lead ill to terminal T of switch T. Terminal 8;, is also connected via leadlllZ to the positive terminal of the battery cell B It is also noted that a jumper wire M3 is connected between terminal 5,, and S and is show in broken lines since such is interally within the switch and is a part of the switching element when purchased. All of the leads shown in the full line have to be supplied when wiring up the switches, whereas, those shown in broken lines are part of the switch when purchased. Terminal S is connected via lead 114 to the negative terminal of cell B Terminal S is also connected to terminal S through the internal lead 115. Terminal 8, is connected via lead ll 16 to the positive terminal of cell l3 and connected via lead M7 to terminal T of switch T. An internal lead I18 also extends between terminals 5-, and S Terminal S is connected via lead I19 to the negative terminal of cell 3,. An internal connection, such as via lead 129, extends from terminal S to S Terminal 5,, is connected via lead 121 to the positive terminal of cell B Terminal S is connected via lead 122 to the negative terminal of cell B Terminal S is also connected via lead 123 to terminal T of switch T. Terminal S is connected via lead 12 is connected via lead 124 to the positive terminal of cell B Terminal 5,, is connected via lead 125 to the negative terminal of cell B and is also connected via lead 126 to terminal T of switch T.

Referring to switch T lead 127 extends from terminal T to T and internal leads 128 and 129 extend between terminals T and T and T and T respectively.

A jack 130 is interposed in the leads connecting the switches to the battery so that the battery can be removed and a new one substituted therefor during the recharging. As previously mentioned, the wiring is such that by sequentially operating the switches R, S and T respective voltages of 6, l2 and 24 volts can be applied to the motor D so as to vary the speed of such. When the switching element 99 of switch R is moved from the left-hand side to the right-hand side all of the cells Bl through B4 are connected in parallel thus, 6 volts is applied to the motor D. When the switching element 162 of switch S is moved to the right with the switching element 99 of switch R, then 12 volts is supplied to the motor D since two of the cells are connected in parallel and then the two groups of two cells are connected in series so as to place 12 volts on the motor D.

When the switching elements of all three switches R, S and T are moved to the right then the cells Bl through B4 are connected in series and 24 volts is supplied to the motor D.

In operation the operator stands on the platform 22 and when he shifts his weight to the rear of the platform such causes the braking shoe 68 to be moved out of engagement with the wheel C. I-le ten pushes forward on the throttle 15 causing a voltage to be applied to the motor D. .When the motor D is energized such, in turn, drives the wheel B through the chain 49 and the large sprocket 25. The vehicle is steered by manipulating the steering wheel 14. If the vehicle is turned too sharply, sometimes it will tend to tilt. However, due to the stabilizing members F such engage the surface in which the vehicle is traveling minimizing the chance of such turning over.

While a preferred embodiment of the invention has been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.

I claim:

1. A self-propelled vehicle capable of riding on rigid surfaces comprising: a frame; a pair of opposed circular angle members in juxtaposition defining a channel therebetween; ball bearings carried within said channel for allowing said angle members to rotate relative to each other about a vertical axis; one of said channel members being fixed to said frame adjacent one end thereof; a steering wheel mounted for rotation on an axle, said axle being carried by said other channel member for rotating therewith relative to said one channel member in order to steer said vehicle; and said other channel member having a groove adjacent the outer perimeter thereof; a cable carried in said groove and wrapped around said other channel member; means for pulling said cable so as to rotate said other channel member in order to steer said vehicle; a pair of wheels carried on the opposite 'end of said frame from said steering wheel in engagement with said surface upon which the vehicle is traveling for supporting said opposite end of said vehicle; and a motor mounted on said frame in driving engagement with at least one of said wheels so that when such is energized the vehicle is propelled. l

2. The vehicle as set forth in claim 1, further comprising: vertically spaced inwardly extending locking abutments carried by said opposed icircular angle members on opposite sides of said ball bearing for restricting vertical movement of said angle members relative to each other 1 3. The vehicle as set forth in claim 1, further comprising laterally extending stabilizing members carried by said frame adjacent and on opposite sides of said steering wheel, said stabilizing members being spaced vertically from said surface upon which said vehicle is riding but engages said surface when said vehicle tilts to one side preventing said vehicle from turning over. 5 

1. A self-propelled vehicle capable of riding on rigid surfaces comprising: a frame; a pair of opposed circular angle members in juxtaposition defining a channel therebetween; ball bearings carried within said channel for allowing said angle members to rotate relative to each other about a vertical axis; one of said channel members being fixed to said frame adjacent one end thereof; a steering wheel mounted for rotation on an axle, said axle being carried by said other channel member for rotating therewith relative to said one channel member in order to steer said vehicle; and said other channel member having a groove adjacent the outer perimeter thereof; a cable carried in said groove and wrapped around said other channel member; means for pulling said cable so as to rotate said other channel member in order to steer said vehicle; a pair of wheels carried on the opposite end of said frame from said steering wheel in engagement with said surface upon which the vehicle is traveling for supporting said opposite end of said vehicle; and a motor mounted on said frame in driving engagement with at least one of said wheels so that when such is energized the vehicle is propelled.
 2. The vehicle as set forth in claim 1, further comprising: vertically spaced inwardly extending locking abutments carried by said opposed circular angle members on opposite sides of said ball bearing for restricting vertical movement of said angle members relative to each other.
 3. The vehicle as set forth in claim 1, further comprising laterally extending stabilizing members carried by said frame adjacent and on opposite sides of said steering wheel, said stabilizing members being spaced vertically from said surface upon which said vehicle is riding but engages said surface when said vehicle tilts to one side preventing said vehicle from turning over. 